Background: This study presents data on the characteristics of the Camberwell Cohort, 25 years after they were first assessed in the 1970s [Wing & Gould (1979) "Journal of Autism and Childhood Schizophrenia" vol. 9, pp. 11-29]. It also presents data on changes over time which adds to that presented in Beadle-Brown et al. ["Journal of Intellectual Disability Research" (2000) vol. 32, pp. 195-206]. Methods: Measures of level of skills, ability and behaviour, including self-care, educational, social skills, cognitive ability and challenging behaviour, were conducted with as many of the cohort as possible. In addition, background information was collected on diagnosis, placement history, daytime activity and family contact. Results: The cohort (n = 91) now aged between 27 and 42 years were living mostly in the community (68%) or with their parents (27%). Sixty-four per cent of the sample who could be tested (n = 36) had an IQ below 50, 73% were socially impaired and 72% had some form of autistic spectrum disorder. There were few changes over time between time 2 (1980s) and time 3--as reported in Beadle-Brown et al., most changes occurred during childhood and early adolescence. However, for those who had been in institutional care for more than 3 years, there were a number of self-care skills which significantly increased between time 2 and time 3 (after a move into the community).